Apparatus for making molds.



G. E. BURNS.

APPARATUS FOR MAKING MOLDS.

APPLICATION FILED APR. 1, I912.

1,098,311. Patented May 26, 1914.

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2? 7 A W A GEORGE E. BURNS, OF CENTRAL FALLS, RHODE ISLAND.

APPARATUS FOR MAKING MOLDS.

Specification of Letters Patent.

Patented lilay 26, 191 1.

Application filed April 1, 1912. Serial No. 887,604.

To all whom it may concern Be it known that I, GEORGE E. BURNS, a citizen of the United States, residing at Central Falls, in the county of Providence and State of Rhode Island, have invented new and useful Improvements in Appara tus for Making Molds, of which the following is a specification.

This invent'on has for its object the pro-- duction of novel apparatus for making molds for casting finger rings.

In accordance with my invention I have provided means for confining aring pattern on a holder which acts to form in the moldable material employed a core print, in the bottom of which print the pattern ring makes its counterpart impressionto receive the molten metal in casting the ring to be made. The ring pattern shown has at its head a crown or wider part; and the invention includes means for positioning the ring accurately in the center between the two sides of the mold.

The molds are made in two halves and put together by reversing one half and placing it on the other, in order thatthe complete ring may be cast from the mold. After the mold has been formed in the apparatus hereinafter described, it is baked and the two halves put together and the ring cast in the usual manner. It is essen tial, therefore, that the device should accurately position the ring pattern between the two sides of the mold in order that when one of the half molds is reversed and placed on the other, the impressions of the half ring in each will exactly aline one with the other, so that, when cast, the complete ring will be perfect;

The invention consists in an apparatus of the character described in the specification and particularly set forth inthe claim.

Referring to the'drawings: Figure 1 is a.

plan view of a mold embodying my invention, with a finger ring pattern in position on the core print former. Fig. 2 is a sectional elevation taken on line 2-2 of Fig. 1. Fig. 3is a sectional elevation taken on line 33 of Fig. 1. Fig. 1 is a detail section taken on line 4 -4 of Fig. 2. Fig. 5 is a detail section taken on line of Fig. 2. Fig. 6 is a detail plan view of the upper positioning plate. Fig. 7 is a detail plan View of the lower positioning plate. Fig. 8 is a detail underneath plan of the core print former. Fig. 9 is a plan view of one of the half molds broken away at the ends to save space. Fig. 10 is a section of two of the molds with a core in position and in readiness for, casting a ring. Fig. 11 is a detail side elevation of the core print former.

Like numerals refer to like parts throughout the several views; of the drawings. I

In the drawings, 11 is a basewith two vertical side walls 12 projecting upwardly therefrom and detachably fastened thereto, the upper edges 13 of said side walls being inclined at an angle. print former 14: is mounted on said base 11, the central portion 15 of said core print A cylindrical core former being of such length as to fit accurately between the inner faces of the two side walls 12 and the opposite ends .16 of said core print former being of less dia- 'meter than the central portion 15 thereof and mounted in semi-cylindrical recesses 17 provided in the upper edges 13 of said side walls 12. The ends 16 are preferably. cut to form semi-cylindrical projections to fit the semi-cylindrical recesses 17.

The core print former 14 is locked in position upon the base 11 by pins 18 fast to the side walls 12 and projecting into corresponding holes in the ends 16. A keyway19 is provided in the periphery of the central portion 15 of the core print former 14 and extends the entire length of said central portion and in this keyway is a key 20, whereby aring 21, constituting a pattern, may be locked in position-upon the core print former. Whileitis preferable to have the ring which is used as a pattern fit the central portion 15 of the core print former 14, still, if it is slightly loose upon said central portion, it may be fixed rigidly thereto by means of the key 20. The ring 21 is positioned midway between the two ends of the core print former and, therefore, midway between the side walls 12, by suitable accurate measuring instruments and the same is located circumferentially of the former by alining the center of the crown portion of the ring with a line a. extending longitudinally of the core print former, said line lying in the same plane as that in which the iiatted upper faces of the ends 16 lie.

Stop plates 22 and 23 are provided, the upper stop plate 22 being adapted to slide in ways 24: formed in the side walls 12 (see Fig. i). The lower stop plate 23 is adapted to slide in Ways also provided in said side walls 12. The lower stop plate 23 has a T- shaped projection or rib 26 thereon which extends across the upper surface of the lower stop plate and projects beyond the opposite edges of said stop plate, as seen in Fig. 7 to extend across the upper edges of the side walls 12. This projection makes a print in the mold, constituting a runway, whereby the metal can pass from the exterior of the mold to the space surrounding the core print in order to cast the ring.

A notch 27 is provided in the lower stop plate 23 and the ring 21 fits into this notch, while the crown 28 on the ring pattern fits into another notch 29 in the upper stop plate The lower stop plate 23 is locked in position relatively to the base by a screw having screw-threaded engagement with one of the side walls and bearing against one edge of the plate 23. A similar means may be employed to lock the upper stop plate to the side walls, if desired, but ordinarily this is not necessary.

Surrounding the base 11 is a casing 31, the walls of which project upwardly beyond the side walls 12 of the base 11. This casing is open at its upper end to receive moldable material, as at 32. The inner faces 33 of the walls of the casing 31 are tapered inwardly, as seen in Figs. 2 and 3, and handles 34; are fastened to said casing by means of which it may be manipulated, as hereinafter described.

The general operation of the apparatus hereinbefore described is as follows: A pattern ring 21 is placed upon the core print former let and located centrally thereon between its two ends, as hereinbefore described, and also as described with the center of the crown of the ring in alinement with the line (6. Said core print former is placed in position with its ends 16 resting in the semicylindrical recesses 17 in the upper edges 13 of the side walls of the base 11. The pins 18 serve to keep this core print former from turning. The stop plates 22 and 23 are moved toward the core print former until one portion of the ring rests in the recess 27 of the lower stop plate and the crown or head of the ring rests in the recess 29 of the upper stop plate. The plate 23 is then looked in position by the screws 30 and said ring pattern is locked in its central position by means of the key 20, and suitable material to form the mold is placed in the easing 31 and thoroughly tamped down around the projecting upper half of the ring pattern. The casing 31 is then lifted by means of the handles 34, lifting the mold with it by reason of the tapered inner faces 33 of said casing. l'Vithin the mold will then be formed a semi-cylindrical recess 35 (see Fig. 9) and also an imprint of one-half of the ring pattern 21 and an imprint constituting the runway 39. Any desired number of half molds will be thus formed. These half molds are then baked to render them hard and they are then utilized to cast any desired number of rings which may be done by placing a core 36 in the recess 35 in one of the half molds 37. The other half mold 38 (Fig. 10) will then be placed on top of the half mold 37, making the complete mold, with the core 36 inserted therein. Metal now being poured into the mold will pass along the runway 39 into the space surrounding the core 36 and into the imprint 40 of the ring formed in the two half molds 37 and 38. Thus the complete ring will be cast and is removed from the mold and finished in the usual manner well known to those skilled in this art.

By having the upper edges of the walls of the base inclined at an angle and the stop plates 22 and 23 also inclined at an angle, a ring provided with undercut engraving on its sides may be copied, but it is not necessary that the upper edges of the walls should be inclined except for reproducing a ring with undercut portions in its surface. Otherwise, the upper edges of the side walls of the base could be horizontal.

Having thus described my invention, what I claim and desire by Letters Patent to secure is:

An apparatus of the character described having, in combination, a base, with two vertically disposed side walls having inclined upper edges, a cylindrical core print former the opposite ends of said core print former being of less diameter than the central portion thereof and mounted in semicylindrical recesses provided in the upper edges of said side walls, said central portion fitting between said side walls, a ring applied to said core print former and stop plates on opposite sides of said core print former, said stop plates being slidable on said base, transversely of said core print former, and adapted to engage opposite sides of said core print former and ring.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

GEORGE E. BURNS.

Witnesses:

CHARLES S. Goonnve, SYDNEY E. TAF'r.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington D. C. 

